【摘要】 目的:采用CBCT评价下颌第三磨牙引导管的形态,探究其与阻生状态的关系,为预测第三磨牙是否阻生提供依据。方法:选取76例下颌第三磨牙的CBCT影像资料,测量其引导管长径、短径、长短径之比及其与牙胚长轴的角度,并对测量数据进行统计分析。结果:不同阻生状态下颌第三磨牙的引导管之间,长径、短径和长短径之比无统计学差异,与牙胚长轴的角度:正常萌出>近中阻生>水平阻生。下颌第三磨牙引导管的长径、短径及其与牙胚长轴的角度与年龄相关。结论:CBCT可以精确评价引导管形态,不同阻生状态的第三磨牙引导管与牙胚长轴的角度不同。引导管的缺失和/或与牙胚长轴的角度异常,提示牙齿可能出现萌出异常。更多还原

【Abstract】 Objective: To evaluate the shape of gubernacular canals(GCs) and its relation to impaction of mandibular third molars by CBCT. Methods: 76 CBCT image data of mandibular third molars were included. The long diameter, short diameter, ratio of them, and angulation of GCs to tooth axis were measured and analyzed. Results: There was no statistical difference in long diameter, short diameter, and ratio of them between the groups. The angulation of GCs to tooth axis: normal eruption > mesioangular impaction > horizontal impaction. The long diameter, short diameter, and angulation of GCs to tooth axis were related to the age in mandibular third molars. Conclusion: CBCT can accurately measure the shape of GCs. The angulation of GCs to tooth axis differs in mandibular third molars with different impactions. The absence of GCs, and/or an abnormal angle to the long axis of the tooth may suggest the abnormal eruption.更多还原